Locating, marking and drilling at the center point of different shaped objects is a common practice in the woodworking and metalworking industries and is performed by lathe operators, carpenters, tool makers, hobbyists and other technicians.
A lathe operator marks the center at both ends of a billet to properly position the billet in a lathe. A carpenter locates the center at the end of a 4×4 wood column and drills a hole for receiving a stud or bolt. The hobbyist needs to mark the center at the end of a small diameter dowel to drill a hole through the dowel.
Traditionally locating and marking the center point on objects has been by positioning a center square or straight edge device on the object and making pencil lines or scribe marks at right angles as shown in U.S. Pat. No. 477,959 issued to Price and U.S. Pat. No. 1,157,589 issued to Savage, the center being the intersection of the lines drawn. Other devices have been developed as shown in U.S. Pat. No. 49,553 to Safford et al; U.S. Pat. No. 311,619 to Varnum; U.S. Pat. No. 316,918 to Standeford; U.S. Pat. No. 335,846 to Singer; U.S. Pat. No. 352,693 to Irving; U.S. Pat. No. 364,082 to Bell; U.S. Pat. No. 390,658 to Gage; U.S. Pat. No. 578,196 to Beck; U.S. Pat. No. 597,915 to Roosa; U.S. Pat. No. 787,893 to Christoph; U.S. Pat. No. 834,973 to Fisk; U.S. Pat. No. 906,180 to Wrightsman; U.S. Pat. No. 912,052 to Albertson; U.S. Pat. No. 986,405 to Oneal; U.S. Pat. No. 1,067,877 to Needham; U.S. Pat. No. 1,187,658 to Sauerhering; U.S. Pat. No. 1,274,647 to Whipple; U.S. Pat. No. 1,280,379 to Bonney; U.S. Pat. No. 1,286,748 to Ozerowicz; U.S. Pat. No. 1,386,152 to Brigham; U.S. Pat. No. 1,543,093 to Bickl U.S. Pat. No. 2,413,768 to Hyde; U.S. Pat. No. 2,559,280 to Cochran; U.S. Pat. No. 2,479,912 to Desy; U.S. Pat. No. 2,599,819 to Fisher; U.S. Pat. No. 2,816,366 to Barlow; U.S. Pat. No. 4,326,339 to Marino; U.S. Pat. No. 4,667,549 to Griffin; and U.S. Pat. No. 4,868,995 to Lee.
Many of the techniques used by these devices comprise complicated mechanisms and require multiple and often awkward manipulations including but not limited to measuring, layout and setup. Review of prior art clearly portrays the use of gears, rack and pinions, set screws, ruler lines, turn handles, threaded rods and other mechanisms. U.S. Pat. No. 4,868,995 discloses a simple device, but it requires being mounted to a wall and is basically only for wood parts that fit into a lathe. It is not suitable for marking small parts which are shorter in length than orthogonal plates. It would be difficult if not impossible to mark the end of a 4×4 wood column that is 8 feet long. The patent notes when it refers to rectangular objects that it can “ . . . assist in locating the center . . . ” and the object is “ . . . slightly rectangular . . . ”.
The U.S. Pat. No. 316,918 to Standeford describes a device having more latitude. It will find the center of a rectangular object, although again, it requires many manipulations with the use of set screws.
U.S. Pat. No. 4,326,339 issued to Marino describes an invention that requires awkward manipulations with pulley and rack and pinion systems. This invention notes a “center point marker” but locates the center line of an object from only two ends, not a center point equal distance from all perimeter edges of the object; and further, it has no element for making a mark.
Although U.S. Pat. No. 568,196 issued to Beck illustrates a jaw method in the form of a cross, it requires a rack and pinion system for moving the jaws and does not address marking the center of a rectangular object.
U.S. Pat. No. 4,084,325 issued to Jones Jr. locates the center of objects; however, it requires several awkward manipulations using set screws.
U.S. Pat. No. 2,348,878 to Summers locates the center of objects requiring many awkward manipulations using set screws and scale graduations.
U.S. Pat. No. 2,348,878 issued to Behen locates the center of a shaft and also requires sets screws bolts and has a loose bushing mounted in slots.
U.S. Pat. No. 5,437,105 issued to Work locates only a parallel line center from two parallel edges of an object.
U.S. Pat. No. 6,158,137 issued to Bramlett is a complicated mechanism with multiple elements using gears and scale graduations.
U.S. Pat. No. 3,345,755 issued to Ferebee employs racks and gears and is complicated to the point of being commercially unfeasible.
Heretofore, prior art fails to address a device that simply clamps to the object in one manipulation to locate the center thereof.
It is therefore an object of the invention to provide a simple device for locating the center of square, round, octagonal, hexagon, rectangular and other regular polygon objects with an even number of sides.
It is another object of the invention to provide a plurality of means for moving a center punch to the center of an object.
It is another object of the invention to provide a center point locator device that centers a drill bushing to an object, to guide a drill bit for drilling a hole.
It is another object of the invention to provide a center point locator device that clamps to the object.
It is another object of the invention to provide a center point locator device that has a center punch for marking the center of an object.
It is further object of the invention to provide a spring to hold and return the center punch to the neutral position.
It is another object of the invention to provide control means for moving sliding jaws together.
It is another object of the invention to provide means for guiding sliding jaws to the center.
It is another object of the invention to provide slot apertures in the jaws and the bed plate to maintain alignment.
It is another object of the invention to provide a center point locator device that locates the center of a rectangular part.
It is another object of the invention to provide a center point locator device that locates the center of a hexagon shaped part.
It is another object of the invention to provide a hand held center point locator device.
It is another object of the invention to provide a portable center point locator device.
It is another object of the invention to provide a center point locator device that does not require calibrated measuring lines.
It is another object of the invention to provide a center point locator device that does not require lock screws, gears, rack and pinions and crank handles.
It is another object of the invention to provide a center point locator device that is light weight.
It is another object of the invention to provide a center point locator device that is inexpensive to fabricate.
It is another object of the invention to provide a center point locator device that can be fabricated in different sizes.